1. Field of the Invention
The present invention relates to a tray transferring apparatus, and more particularly to, an improved tray transferring apparatus which can stably transfer semiconductor devices not separately from a handling tray during the transferring operation of the handling tray, by gripping a fixed tray by a first fixing member, correcting right/left inclination of the clamped fixed tray by a correcting means, and covering the upper portion of the handling tray with the clamped fixed tray.
2. Description of the Background Art
In general, tests for detecting defects are executed on semiconductor devices completed on production lines before forwarding. A horizontal handler is used to test various logic devices, such as quad flat packages (QFP), ball grid arrays (BGA), pin grid arrays (PGA) and small outline packages (SOP) which are non-memory semiconductor packages among the semiconductor devices.
The horizontal handler automatically horizontally moves the devices on a tray between the processes, mounts the devices on a horizontally-disposed test socket of a test site, executes a wanted test thereon, classifies the devices into various levels according to the test results, and unloads the devices on the tray.
On the other hand, recently, there have been increasing demands for the semiconductor devices stably operated in a specific temperature environment such as a high or low temperature as well as a normal temperature. Accordingly, the horizontal handler is also required to test performance of the semiconductor devices in a wanted temperature of users.
In order to test the semiconductor devices in the high or low temperature, the tray on which the semiconductor devices are mounted needs to be stably transferred.
In the case that small-sized semiconductor devices are transferred by a handling tray to be tested in the handler, the semiconductor devices are frequently scattered or bounced from the handling tray.
It results from the small size (light weight) of the semiconductor devices.
A conventional tray transferring apparatus has been disclosed under Korean Laid-Open Patent Registration 10-0381854.
The conventional tray transferring apparatus for transferring the tray in the handler will now be explained with reference to FIG. 1.
FIG. 1 is a schematic perspective view illustrating the conventional tray transferring apparatus.
Referring to FIG. 1, a base plate 10 is moved in the X axis direction by rotation of a ball screw 11 installed on the base plate 10 in the X axis direction, and two sheets of first and second support plates 20 and 30 are installed through linear guides 12 extended in the Z axis direction on one surface of the base plate 10.
Here, the first and second support plates 20 and 30 are moved in the Z axis direction by driving of first and second cylinders 21 and 31 positioned below them. A plurality of guide pins 22 are appropriately disposed on the edges of the upper portion of the first support plate 30, thereby guiding the edges of the tray 1 to be stably mounted on the first support plate 20.
In addition, hooks 32 are disposed in the edges of the lower portion of the second support plate 30 to clamp the tray 1.
A hook apparatus 33 connected to the upper portions of the hooks 32 of the second support plate 30 rotates the hooks 32 to the inside/outside of the second support plate 30. A cylinder 34 connected to one end of the hook apparatus 33 drives the hook apparatus 33.
The hook apparatus 33 includes an H-shaped frame 33a, four pins 33b installed to face each other in both ends of the frame 33a, and four shafts 33c rotatably connected to each pin 33b. The hooks 32 are rotated in the forward/backward direction by the hook apparatus 33, to clamp/release the tray 1.
The first and second support plates 20 and 30 sense existence/absence of the tray 1 by proximity sensors 23 and 35 disposed in the outsides thereof.
The conventional tray transferring apparatus can transfer the empty tray 1 by using the first support plate 20, and the tray 1 on which electronic components (not shown) are mounted by using the second support plate 30.
The second support plate of the conventional tray transferring apparatus uses the hooks rotated by the hook apparatus to clamp the tray. However, the hooks do not precisely support the whole tray but support the bottom surface of the tray. Accordingly, when the tray is transferred, the position of the tray is changed by shaking of the apparatus. As a result, a pickup apparatus for picking up the electronic components cannot precisely pick up the electronic components.
In addition, the conventional tray transferring apparatus transfers the tray on which the electronic components are mounted and the empty tray in the clamped and mounted states at the same time. Therefore, the conventional tray transferring apparatus is not easily installed due to the complicated structure. A weight of the apparatus also increases.
Furthermore, the conventional tray transferring apparatus uses many components for transferring the tray, which increases manufacturing expenses.